The opinion of the Vilna Gaon in setting up the seder plate is that the shankbone and the egg are placed closest to the person leading the Seder, the two matzos (the Vilna Gaon did not use the third matzo) are placed in the middle, and the maror and charoses are on the other side. (The karpas is not placed on the ke'arah, and the ke'arah is only brought to the table for Yachatz, after eating the karpas.) thus, it would look like this:
[picture from this English Haggada]
Does anyone know where i can procure a Kaarah made according the opinion of the Vilna Gaon?